This invention relates to hand-held tape dispensers, and particularly to hand-held tape dispensers for adhesive tape of the sort which is used for ordinary household and office purposes. The invention particularly is directed to tape dispensers for dispensing household tape, where the dispenser has a selectively operable brake mechanism to preclude unwanted dispensing or unreeling of the tape, especially when it is being cut. The present invention also provides for tape dispensers which have an improved cutter.
Two kinds of tape dispenser are generally known, for two different kinds of tape. One kind of tape is wide tapexe2x80x94typically 6 to 10 cm wide, of the sort which is typically used to seal boxes and cartons, and the like. Many applications of such tape are from automatic machines; however, there are also many hand-held dispensers of the sort which are particularly used in warehouses and stores, for purposes of assembling and/or sealing boxes.
The other kind of adhesive tape which is in very wide usage, and for which the present invention is particularly intended, is that which is used for household or office purposes. Typically, such tape ranges from 1 to 2 cm in width, and may have varying degrees of tackiness depending on whether the tape is intended for permanent use or temporary use. Some such tapes may have a high gloss, others may have a low gloss such that they may be written on and are essentially invisible to imaging equipment such as photocopiers and facsimile machines.
For purposes of the present invention, such adhesive tape is referred to herein as xe2x80x9chousehold tapexe2x80x9d. Household tape is generally sold and available in two formats: in rolls that are typically sold in boxes, for the purpose of being placed in a dispenser; and already installed in a dispenser. Dispensers, particularly of the hand-held variety, are generally formed of a moulded plastics material, and may or may not be capable of being disassembled for purposes of installing a new roll of adhesive tape therein. It is that kind of hand-held dispenser which is particularly the subject matter of the present invention.
Even such dispensers as are described immediately above may have metal cutters, although generally they are formed with an integral plastic cutter. Metal cutters are more likely to be found, however, on desktop dispensers which are generally very heavy, and into which a roll of household adhesive tape is placed to be dispensed therefrom. Also, metal cutters may be found on older tape dispensers from before 1990 or so.
Of course, any tape dispenser which has a metal cutter generally is such that it has a superior ability to cut tape due to the cutter""s sharper and thinner construction; but such tape dispensers are more expensive to manufacture. Even if it were possible to provide plastic cutters which have significant sharpness, they become dull in use, and present somewhat of a dangerxe2x80x94especially to the fingers of young children who might well be using household adhesive tape in their play, or for a school project or the like.
Plastic cutters may also accumulate shreds of adhesive tape or particles of adhesive, over time, and become somewhat clogged as a result. On the other hand, it has been discovered that if a plastic cutterxe2x80x94especially one which is molded integrally with the structure of the tape dispenserxe2x80x94is wider than the adhesive tape by at least about 25%, then after the adhesive tape has been unreeled it is possible to achieve a satisfactory cutting effect.
Of even greater concern in most instances is the fact that hand-held adhesive tape dispensers tend to overrun when the tape is being dispensed by pulling on the outer end thereof and unreeling the tape from the roll mounted on a hub within the tape dispenser. Still further, because of the somewhat loose condition of the free end of the tape between where it has left the roll and the cutter, and due particularly as well to the general dullness of plastic cutters, obtaining a clean cut of a particular desired length of tape may be difficult. Quite often, considerable manual dexterity is required, with some experimentation as to aligning the length of the tape which is to be cut from the roll at a particular angle either diagonally or vertically with respect to the cutter.
It has been observed that such difficulties, particularly when the adhesive tape is to be cut, can be overcome by applying some kind of braking action to the unreeled portion of adhesive tapexe2x80x94generally by pressing down with a finger on the tape just behind the cutting edge of the cutter on the dispenser. Even that arrangement is unsatisfactory, requiring considerable manual dexterity, and patience. On the other hand, a braking action applied to the roll of tape, and particularly to the hub on which the adhesive tape has been spirally wound, will achieve the desired braking effect on the tape as it is being cut, thereby permitting an easier cut. Still further, applying minimal braking action on the hub, while at the same time unreeling adhesive tape from the hub, can result in a very specific length of tape being unreeled and cut, if necessary.
It is possible to provide an adhesive tape dispenser for household adhesive tapes where one or both sides of the dispenser has certain flexibility, whereby a braking action can be applied against one or both sides of a roll of tape, or against one or both ends of the hub on which the tape has been spirally wound. Moreover, as a roll of tape is unreeled its diameter becomes smaller, and therefore the side surface of the roll of tape becomes smaller and a braking action against the side of the roll of tape may become less effective. Still further, depending on the conditions in which the tape has been made, spirally wound on the hub, and stored, it is possible that a deposit of adhesive might develop on the inside surface of the side of the tape dispenser if the side has been intermittently pressed against the side surface of the roll of tape, and that condition might cause considerable difficulty in smoothly unreeling adhesive tape away from the roll.
Another manner of applying a braking action is to have a brake element which may selectively be applied against the circumference of the roll of tape. However, because the diameter of the roll of tape decreases as tape is unreeled therefrom, a considerable amount of travel is required for the braking element, especially when the last portions of the adhesive tape are being unreeled from the roll and off the hub on which they have been spirally wound.
Several representative examples of tape dispensers, both for industrial and commercial tape which tends to be fairly wide, as noted above, and for narrower household tape, are noted below.
Schleicher U.S. Pat. No. 4,238,272 issued Dec. 9, 1980 teaches a tape dispenser of the sort which may apply either to wide or narrow adhesive tapes, but is particularly of the sort which has relevance to narrow or household adhesive tapes. The device includes a post which extends between panels which are tear-drop shaped and between which the spool of tape is mounted, with the post being mounted in a position which is intermediate the spool of tape and a slot at the end of the dispenser through which the tape is dispensed directly onto a surface. A spring member is attached to the post, with one end having a serrated cutting edge and anvil which are disposed in the slot opening, and the other end impinges resiliently on the supply roll to act as a brake when a cutting action is undertaken.
Mathna et al U.S. Pat. No. 4,729,518, issued Mar. 8, 1988, teaches a tape dispenser of the sort which is a hand-held dispenser typically used for household adhesive tapes, and has a housing with hub and a roll of tape which is journaled on the hub. A paper backcard is disposed around one end of the hub and has a plurality of generally triangular projecting portions which project between the hub and the core. Those projections provide a friction brake between the hub and the core which thereby restricts rotation of the hub to an extent that unwanted rotation of the hub and uncoiling of the tape when it is withdrawn from the dispenser will be precluded. A metal cutter is included.
A self cutting tape dispenser, of the sort which may particularly be useful in commercial and industrial applications, is taught in Arnold U.S. Pat. No. 5,171,397, issued Dec. 15, 1992. Here, the tape dispenser has a moveable cover and a keeper which slides into a circumferential housing so as to keep a roll of tape on an axle. A brake plate is provided, and is such that when tape is being dispensed the thumb is inserted into an opening so as to push the brake plate against the circumference of the roll of tape. In fact, the roll of tape is pushed against the housing back at a time when a tape-cutting blade at the outside wall of the dispenser is pushed against the tape and given a twist so as to cut the tape. The dispenser is intended for one hand operation, and is easily refillable.
Another patent which particularly is directed to a hand-held dispenser used for dispensing industrial or commercial adhesive tape is Luhman et al U.S. Pat. No. 5,754,342, which provides a brake assembly that has a curved brake actuator and a flat brake plate. The structure acts to inhibit free rotation of the tape roll, and therefore the further dispensing of adhesive tape from the roll, when the operator applies pressure by squeezing with the thumb against the brake actuator so as to bend the brake plate about the tape roll and to increase pressure against the tape roll so as to facilitate tape cutting or tape stretching.
The present invention provides a tape dispenser for dispensing rolled adhesive tape mounted on a hub. The hub on which the rolled adhesive tape comprises an inner cylindrical wall, an outer cylindrical wall, and a centrally located radially extending wall between the inner and outer cylindrical walls, and has a wide xe2x80x9cIxe2x80x9d cross-section. There is an annular void formed between the inner and outer cylindrical walls at each side of the radially extending wall. The adhesive tape is spirally wound on the hub.
The tape dispenser comprises a first side member, a second side member, and a cutter member. Each of the first and second side members has a first major side portion which overlies a roll of adhesive tape within the tape dispenser, and a second minor side portion at an end of each first and second side members which is remote from the first major side portion.
The cutter member is mounted between the second minor side portions of the first and second side members.
At least one of the first and second side members has a first cylindrical axle portion formed centrally on the inside surface of the first major side portion thereof and upstanding therefrom.
The other of the first and second side members may also have a second cylindrical axle portion formed centrally on the inside surface of the first major side portion thereof also upstanding therefrom. In that case, the first and second cylindrical axle portions are dimensioned so as to fit one inside the other when the first and second side members are assembled together.
At least the first side member has at least one brake spoke upstanding from the inside surface of the first major side portion thereof. The at least one brake spoke is arranged so as to be radially extending away from the first cylindrical axle portion and spaced away from the first cylindrical axle portion.
Typically, there is a plurality of brake spokes upstanding from the first major side portion of the at least first side member, but not necessarily.
At least the first side member is flexible in the region of the first major side portion thereof, so as to be capable of flexing inwardly in a direction towards the second side member.
When the at least flexible first side member is flexed towards the second side member, the brake spokes extend into the annular void which is on the side of the hub which faces the first side member, so as to cause frictional engagement between the plurality of brake spokes and at least one of the inner and outer cylindrical walls of the hub.
Thus, a braking effect is imparted to the hub so as to preclude unreeling of the spirally wound adhesive tape from the hub.
Typically, the cutter member is formed integrally with one of the first and second side members.
Also, the first and second side members are typically formed of a moulded plastics material.
The first and second side members may be disassembled one from the other so as to replace a hub from which adhesive tape has been unreeled with another hub having adhesive tape spirally wound thereon.
In some embodiments of the tape dispenser of the present invention, a plurality of brake spokes may be formed on each of the first side wall member and the second side wall member.
Generally, however, the brake spokes are formed only on the first side member. Also, a plurality of arcuate ribs may be formed on the inside surface of the first major side portion of the first side member. The arcuate ribs are spaced away from the first cylindrical axle portion, and are interposed among the plurality of brake spokes.
At least one channel may be formed through the thickness of the material of the first major side portion of the first side member, in the region of and extending from each of the arcuate ribs.
In another embodiment, there may be two channels which are formed through the thickness of the material of the first major side portion of the first side member, for each of the arcuate ribs, one of the two channels extending from each end of each of the arcuate ribs.
The first cylindrical axle portion may be dimensioned so as to be fitted inside the second cylindrical axle portion, when the tape dispenser is in an assembled condition.
The configuration of the brake spokes may be such that they will engage the outside annular end surface of the inner cylindrical wall of the hub.
Also, the plurality of brake spokes and the plurality of arcuate ribs may be configured so as to contact the outer cylindrical wall of the hub, and thereby maintain the hub centered over the axle portions.
Typically, there are three brake spokes and three arcuate ribs which are formed on the inside surface of the first major side portion of the first side member.
In particular embodiments of the tape dispenser of the present invention, the second minor side portion of each of the first and second side members is flared upwardly and outwardly in the region of the cutter member. The cutter member has a serrated outer cutting edge which is placed high in the region of the flared second minor side portions, and the width of the cutting edge exceeds the width of the adhesive tape on the hub within the tape dispenser, by at least 25%.
In such a tape dispenser as described immediately above, the cutting edge may be aligned at an angle to each of the flared second minor side portions.
In keeping with another provision of the present invention, a cutter member assembly for a tape dispenser is provided, where the tape dispenser may not necessarily be one which has flexible side members or a specific brake member or braking action. In any event, the cutter member is mounted in an upper region of an end of the tape dispenser which is remote from the region where the hub is mounted. The side members of the tape dispenser are flared upwardly and outwardly in the region of the cutter member, which has a serrated outer cutting edge which is placed high in the region of the upwardly and outwardly flared side members. The width of the cutting edge exceeds the width of the adhesive tape on the hub within the tape dispenser, by at least 25%.
Once again, the cutting edge may be aligned at an angle to each of the upwardly and outwardly flared side members.